A lot of liberal blogs, and a few conservative ones, are discussing this article from the New York Times, which points out that if you look at actual economic resources, instead of prices, increasing health care utilitization isn't going to be so easy, because there's not a lot of spare capacity in the system. Gee, where have I heard this before?
The core problem is that we don't actually have a ton more doctors and nurses. Libertarians (and I think some liberals) argue that the problem is the AMA cartel: they control the number of med school admissions slots. But when I look at the numbers, I don't see all that much room to believe that getting rid of the AMA would let a thousand flowers bloom. In 2008, 42,000 people applied to medical school, and 18,000 enrolled. Presumably some who were admitted decided not to go, and some who weren't shouldn't be doctors. There don't seem to be, say, 10 qualified people for every slot. And nursing schools aren't swamped by more qualified applicants they can handle, yet there's a nursing shortage.
Another problem is that a teaching hospital is a hard thing to construct--given how much training doctors need, we won't do that overnight. Teaching hospitals are very expensive, and receive heavy government subsidies. Obviously, we could increase the number of doctors by some amount, but it wouldn't take care of the supply problem.